I expected something similar, but this seems to happen only on very very few computers. I assume the resolution change takes place during the initial sensor detection phase.
Possible steps to avoid this might be:
1) install the latest nVidia drivers from nVidia web site
2) use the command line switch /NONVIDIAI2C (but any available sensor on the video card will no longer be detected and used).
If you're using any other software that talks to the video card, such as TVTOOL or some manufacturer specific software, it would be nice for me to know.
If you could send me a SEND REPORT (please inform me when you will do so), I will check to see if this might be due to some detection routine that might be writing something in some registers on your video card.

There is a special DEBUG procedure. You can find it explained in the help file. If you follow those steps I might fix this issue with your computer once and for ever, otherwise we might consider it fixed by the /NONVIDIAI2C.
The fact is that there seems to be something that conflicts with SpeedFan when it reads the SMBus. I'm telling you this because a problem during SEND REPORT can only be caused by READs: sending a report does not write anything. Since you're telling me that it freezes while SCANNING PCI (very odd indeed), I would really like to further investigate.
You might try the following command line options:
1) /NOPCISCAN : this will avoid detection of ANY SMBus and you will be able to see your sensors only if they are on the ISA BUS
2) /NOSMBSCAN : this will allow the PCI SCAN, but will end up with very little as the relevant SMBus devices won't be scanned.
By trying a SEND REPORT with /NOPCISCAN we can try to isolate the reason for the hang.
On the other hand: if a SEND REPORT with /NOSMBSCAN works fine, then the problem is not related with PCI SCANNING (I've never seen any problem related to PCI scanning).

Version 4.13 will improve nVidia Video Card support, remove some checks for odd hardware devices and completely remove nVidia Video Card I2C scanning in SEND REPORT.
This way there is no known way to hurt the monitor via SpeedFan.